Licensing is pretty simple.
You pay for the install, and you pay for additional engines.
Depending on the currency, the cost for the install and engines will vary.
There is also an SMB edition which is less expensive, does not allow scaling up by adding engines and is limited to two report developers and 250 users overall.
There is no per-user fee nor is there any charge for designers.
If you're connecting to QlikView documents, you will also need a QlikView license and the desktop software for the initial install and each additional engine.
Hope this is clear.
I know this is an older discussion, but I wanted to share some information that I found while searching for official Qlik documentation regarding NPrinting 17 License information.
1. Qlik >> http://www.qlik.com/us
a. License Terms
On the qlik.com page, scroll to the bottom of the screen, and select "License Terms" under the LEGAL category.
b. Qlik NPrinting License Metrics
On the Qlik License Terms page, scroll down to "Additional Terms" and select Qlik NPrinting License Metrics
2. Qlik Help >> http://help.qlik.com/en-US/
a. Qlik NPrinting 17
On the help.qlik.com page, select your version of Qlik NPrinting. This will open the web-based help for NPrinting.
b. Deploying Qlik NPrinting
When the help page opens, locate the Licensing information under the "Deploying Qlik NPrinting" section.
(The licensing information for your version may be located in a different place. You can always search the help).